The present technology relates to a receiver configured to receive a satellite signal, and more particularly, to a receiver configured to receive satellite signals from different types of satellites.
GPS, Galileo and GLONASS are known as positioning systems adapted to find the position and speed of a mobile using a positioning signal transmitted from a satellite. GPS (Global Positioning System) was developed in the United States and has found application for aviation and marine navigation and as a car navigation system. Galileo is a positioning system developed primarily in the European Union (EU). GLONASS (GLObal NAvigation Satellite System) is a positioning system developed in Russia. Although differing in pseudo noise in spread spectrum modulation of a positioning signal, GPS and Galileo use the same positioning principle and calculations. Further, the two systems are the same in terms of the center frequency of the carrier frequency in a specific frequency band. On the other hand, GLONASS differs from GPS and Galileo in terms of the center frequency of the carrier frequency.
A receiver has been proposed in related art that is designed to receive positioning signals from a plurality of types of satellites of all the positioning systems described above. For example, a receiver has been proposed that can receive GPS and GLONASS positioning signals. This is accomplished by setting a first local oscillation frequency intermediate between the GPS and GLONASS reception frequencies and using an image removal mixer (refer, for example, to Japanese Patent Laid-open No. Hei 07-128423). Further, another receiver has been proposed that is designed to generate intermediate frequencies for a plurality of satellites through a single down-conversion process (refer, for example, to Japanese Patent Laid-open No. 2009-092473). This is accomplished by setting different first mixer frequencies for two reception signals.